The invention relates to a steering column for a motor vehicle, comprising a jacket unit by which a section adjoining a steering wheel-side end of a steering spindle is rotatably supported, and at least one support unit, which, on the one hand, is securable in position on an automobile body-stationary part of the motor vehicle and which, on the other hand, is fixedly connected or fixedly connectable with the jacket unit.
Steering columns which, in the event of a motor vehicle crash, are collapsible one into the other with the absorption of energy in order to lower the risk of injury to the driver, are known in various embodiments. For the adaptation of the seating position at different sizes of the driver, steering columns are frequently utilized that are adjustable in length and/or inclination or height. For reasons of cost, however, simpler nonadjustable steering columns are also employed, which are also said to be collapsible in the event of a crash with the absorption of energy.
U.S. Pat. No. 4,991,871 A discloses, for example, a nonadjustable steering column in which the steering spindle as well as a jacket unit rotatably (bearing) supporting the steering spindle comprise each two sections telescopable with respect to one another. In the event of a crash, the section of the jacket unit closer to the driver is torn out of the vehicle-stationary mounting and, with the exhaustion of energy, is pressed into the section of the jacket unit further removed from the driver. Such an implementation is complex and cost-intensive.
DE 2 363 895 A1 also discloses a nonadjustable steering column in which, in the event of a crash, the jacket unit rotatably supporting a section of the steering spindle is torn out of a vehicle-stationary mounting and pressed against a deformation member, for example a corrugated tube, wherein energy is absorbed. Due to the additionally required energy absorption part, this device is also relatively complex.
An adjustable steering column with an energy absorption mechanism for the event of a crash is disclosed in JP 102 179 81 A. In the closed state of a securement device.
A jacket unit rotatably supporting the steering spindle is fixedly connected with a holding unit. The holding unit comprises a first body-stationary part and a second part which, in the closed state of the securement device, is secured nondisplaceably with respect to the jacket unit. In the event of a crash, the second part of the holding unit can separate from the first part and be dislocated together with the jacket unit in the direction toward the vehicle front. Between the first and the second part of the holding unit is disposed an energy absorption part which, by tearing open along a tear line, absorbs energy in the dislocation of the jacket unit in the direction toward the motor vehicle front.
A similarly implemented energy absorption mechanism is also disclosed in EP 1 707 471 A1 and EP 1 839 994 A2. In each instance between two separate parts of the holding device is a separate energy absorption part. One of the two separate parts is body-stationary and the other part is connected nondisplaceably with the jacket unit. In normal operation, the parts are connected with one another and, in the event of a crash, they can become detached from one another.
In view of the multi-part implementation of the holding units and the separate energy absorption parts, these devices are relatively complex to implement.